Emily L Weiser, Ph.D. (Former Employee)
Science and Products
Counts of Birds in Aerial Photos from Fall Waterfowl Surveys, Izembek Lagoon, Alaska, 2017-2019 Counts of Birds in Aerial Photos from Fall Waterfowl Surveys, Izembek Lagoon, Alaska, 2017-2019
This dataset includes tables summarizing image information and bird counts from the aerial digital images taken over open water at Izembek Lagoon in Alaska in fall 2017-2019. These summaries list one record per image and provide the camera parameters, latitude, longitude, altitude, and automated and manual counts representing the total number of birds in each taxon (brant, white-cheeked...
Nest Survival Bias Analysis Nest Survival Bias Analysis
This R script will run one replicate of one scenario used by Weiser (2021) to quantify biases in estimates of nest survival when nests are not found at the beginning of the nesting interval (age 0). The script simulates nest monitoring histories based on input parameters, applies models with or without an age effect to estimate daily survival rates, and calculates nest survival (to the...
Arctic Shorebird Population Model Arctic Shorebird Population Model
This R script will run one example of the stochastic matrix models run by Weiser et al. (2020) to simulate shorebird populations. The model predicts population growth rates and elasticity values of vital rates. The example script is stand-alone and contains input values for one example species; input values for the other species are provided in the manuscript.
GRTS for Integrated Monarch Monitoring Program Code GRTS for Integrated Monarch Monitoring Program Code
These scripts prepare input files and run a Generalized Random Tessellation Stratified (GRTS) draw to select sampling locations for the Integrated Monarch Monitoring Program in the U.S., Canada, and Mexico.
Filter Total Items: 26
TrendPowerTool: A lookup tool for estimating the statistical power of a monitoring program to detect population trends TrendPowerTool: A lookup tool for estimating the statistical power of a monitoring program to detect population trends
A simulation-based power analysis can be used to estimate the sample sizes needed for a successful monitoring program, but requires technical expertise and sometimes extensive computing resources. We developed a web-based lookup app, called TrendPowerTool (https://www.usgs.gov/apps/TrendPowerTool/), to provide guidance for ecological monitoring programs when resources are not available...
Authors
Emily L. Weiser, James E. Diffendorfer, Laura Lopez-Hoffman, Darius J. Semmens, Wayne E. Thogmartin
Sample-size considerations for a study of shorebird nest survival in the 1002 Area, Arctic National Wildlife Refuge, Alaska Sample-size considerations for a study of shorebird nest survival in the 1002 Area, Arctic National Wildlife Refuge, Alaska
Authorization of lease sales for oil development in the 1002 Area of the Arctic National Wildlife Refuge has highlighted gaps in information about biological communities in the area. The U.S. Fish and Wildlife Service, which is planning a study to evaluate spatial variation in the nest survival of tundra-breeding shorebirds to identify hotspots with high nest survival, sought advice from...
Authors
Emily L. Weiser
Annual adult survival drives trends in Arctic-breeding shorebirds but knowledge gaps in other vital rates remain Annual adult survival drives trends in Arctic-breeding shorebirds but knowledge gaps in other vital rates remain
Conservation status and management priorities are often informed by population trends. Trend estimates can be derived from population surveys or models, but both methods are associated with sources of uncertainty. Many Arctic-breeding shorebirds are thought to be declining based on migration and/or overwintering population surveys, but data are lacking to estimate the trends of some...
Authors
Emily L. Weiser, Richard B. Lanctot, Stephen C. Brown, H. River Gates, Joel Bety, Megan L. Boldenow, Rodney W. Brook, Glen S. Brown, Willow B. English, Scott A. Flemming, Samantha E. Franks, H. Grant Gilchrist, Marie-Andree Giroux, Andrew C. Johnson, Steve Kendall, Lisa V. Kennedy, Laura Koloski, Eunbi Kwon, Jean-Francois Lamarre, David B. Lank, Christopher J. Latty, Nicolas Lecomte, Joseph R. Liebezeit, Rebecca L McGuire, Laura McKinnon, Erica Nol, David C. Payer, Johanna Perz, Jennie Rausch, Martin D. Robards, Sarah T. Saalfeld, Nathan R. Senner, Paul A. Smith, Mikhail Soloviev, Diana V Solovyeva, David H. Ward, Paul F. Wood, Brett K. Sandercock
Evidence for a growing population of eastern migratory monarch butterflies is currently insufficient Evidence for a growing population of eastern migratory monarch butterflies is currently insufficient
The eastern migratory population of monarch butterflies has experienced a multi-decadal decline, but a recent increase in abundance (to 6.05 ha in winter 2018) has led some observers to question whether the population has reversed its long-standing decline and embarked on a trajectory of increasing abundance. We examined this possibility through changepoint analyses, first assessing...
Authors
Wayne E. Thogmartin, Jennifer A Szymanski, Emily L. Weiser
Challenges for leveraging citizen science to support statistically robust monitoring programs Challenges for leveraging citizen science to support statistically robust monitoring programs
Large samples and long time series are often needed for effective broad-scale monitoring of status and trends in wild populations. Obtaining those sample sizes can be more feasible when volunteers contribute to the dataset, but volunteer-selected sites are not always representative of a population. Previous work to account for biased site selection has relied on knowledge of covariates...
Authors
Emily L. Weiser, James E. Diffendorfer, Laura Lopez-Hoffman, Darius J. Semmens, Wayne E. Thogmartin
Is the timing, pace and success of the monarch migration associated with sun angle? Is the timing, pace and success of the monarch migration associated with sun angle?
A basic question concerning the monarch butterfly’s fall migration is which monarchs succeed in reaching overwintering sites in Mexico, which fail—and why. We document the timing and pace of the fall migration, ask whether the sun’s position in the sky is associated with the pace of the migration, and whether timing affects success in completing the migration. Using data from the Monarch...
Authors
Orley R. Taylor, James P Lovett, David L Gibo, Emily L. Weiser, Wayne E. Thogmartin, Darius J. Semmens, James E. Diffendorfer, John M. Pleasants, Samuel Pecoraro, Ralph Grundel
Arctic Shorebird Population Model Arctic Shorebird Population Model
This R script will run one example of the stochastic matrix models run by Weiser et al. (2020) to simulate shorebird populations. The model predicts population growth rates and elasticity values of vital rates. The example script is stand-alone and contains input values for one example species; input values for the other species are provided in the manuscript.
GRTS for Integrated Monarch Monitoring Program Code GRTS for Integrated Monarch Monitoring Program Code
These scripts prepare input files and run a Generalized Random Tessellation Stratified (GRTS) draw to select sampling locations for the Integrated Monarch Monitoring Program in the U.S., Canada, and Mexico.
Science and Products
Counts of Birds in Aerial Photos from Fall Waterfowl Surveys, Izembek Lagoon, Alaska, 2017-2019 Counts of Birds in Aerial Photos from Fall Waterfowl Surveys, Izembek Lagoon, Alaska, 2017-2019
This dataset includes tables summarizing image information and bird counts from the aerial digital images taken over open water at Izembek Lagoon in Alaska in fall 2017-2019. These summaries list one record per image and provide the camera parameters, latitude, longitude, altitude, and automated and manual counts representing the total number of birds in each taxon (brant, white-cheeked...
Nest Survival Bias Analysis Nest Survival Bias Analysis
This R script will run one replicate of one scenario used by Weiser (2021) to quantify biases in estimates of nest survival when nests are not found at the beginning of the nesting interval (age 0). The script simulates nest monitoring histories based on input parameters, applies models with or without an age effect to estimate daily survival rates, and calculates nest survival (to the...
Arctic Shorebird Population Model Arctic Shorebird Population Model
This R script will run one example of the stochastic matrix models run by Weiser et al. (2020) to simulate shorebird populations. The model predicts population growth rates and elasticity values of vital rates. The example script is stand-alone and contains input values for one example species; input values for the other species are provided in the manuscript.
GRTS for Integrated Monarch Monitoring Program Code GRTS for Integrated Monarch Monitoring Program Code
These scripts prepare input files and run a Generalized Random Tessellation Stratified (GRTS) draw to select sampling locations for the Integrated Monarch Monitoring Program in the U.S., Canada, and Mexico.
Filter Total Items: 26
TrendPowerTool: A lookup tool for estimating the statistical power of a monitoring program to detect population trends TrendPowerTool: A lookup tool for estimating the statistical power of a monitoring program to detect population trends
A simulation-based power analysis can be used to estimate the sample sizes needed for a successful monitoring program, but requires technical expertise and sometimes extensive computing resources. We developed a web-based lookup app, called TrendPowerTool (https://www.usgs.gov/apps/TrendPowerTool/), to provide guidance for ecological monitoring programs when resources are not available...
Authors
Emily L. Weiser, James E. Diffendorfer, Laura Lopez-Hoffman, Darius J. Semmens, Wayne E. Thogmartin
Sample-size considerations for a study of shorebird nest survival in the 1002 Area, Arctic National Wildlife Refuge, Alaska Sample-size considerations for a study of shorebird nest survival in the 1002 Area, Arctic National Wildlife Refuge, Alaska
Authorization of lease sales for oil development in the 1002 Area of the Arctic National Wildlife Refuge has highlighted gaps in information about biological communities in the area. The U.S. Fish and Wildlife Service, which is planning a study to evaluate spatial variation in the nest survival of tundra-breeding shorebirds to identify hotspots with high nest survival, sought advice from...
Authors
Emily L. Weiser
Annual adult survival drives trends in Arctic-breeding shorebirds but knowledge gaps in other vital rates remain Annual adult survival drives trends in Arctic-breeding shorebirds but knowledge gaps in other vital rates remain
Conservation status and management priorities are often informed by population trends. Trend estimates can be derived from population surveys or models, but both methods are associated with sources of uncertainty. Many Arctic-breeding shorebirds are thought to be declining based on migration and/or overwintering population surveys, but data are lacking to estimate the trends of some...
Authors
Emily L. Weiser, Richard B. Lanctot, Stephen C. Brown, H. River Gates, Joel Bety, Megan L. Boldenow, Rodney W. Brook, Glen S. Brown, Willow B. English, Scott A. Flemming, Samantha E. Franks, H. Grant Gilchrist, Marie-Andree Giroux, Andrew C. Johnson, Steve Kendall, Lisa V. Kennedy, Laura Koloski, Eunbi Kwon, Jean-Francois Lamarre, David B. Lank, Christopher J. Latty, Nicolas Lecomte, Joseph R. Liebezeit, Rebecca L McGuire, Laura McKinnon, Erica Nol, David C. Payer, Johanna Perz, Jennie Rausch, Martin D. Robards, Sarah T. Saalfeld, Nathan R. Senner, Paul A. Smith, Mikhail Soloviev, Diana V Solovyeva, David H. Ward, Paul F. Wood, Brett K. Sandercock
Evidence for a growing population of eastern migratory monarch butterflies is currently insufficient Evidence for a growing population of eastern migratory monarch butterflies is currently insufficient
The eastern migratory population of monarch butterflies has experienced a multi-decadal decline, but a recent increase in abundance (to 6.05 ha in winter 2018) has led some observers to question whether the population has reversed its long-standing decline and embarked on a trajectory of increasing abundance. We examined this possibility through changepoint analyses, first assessing...
Authors
Wayne E. Thogmartin, Jennifer A Szymanski, Emily L. Weiser
Challenges for leveraging citizen science to support statistically robust monitoring programs Challenges for leveraging citizen science to support statistically robust monitoring programs
Large samples and long time series are often needed for effective broad-scale monitoring of status and trends in wild populations. Obtaining those sample sizes can be more feasible when volunteers contribute to the dataset, but volunteer-selected sites are not always representative of a population. Previous work to account for biased site selection has relied on knowledge of covariates...
Authors
Emily L. Weiser, James E. Diffendorfer, Laura Lopez-Hoffman, Darius J. Semmens, Wayne E. Thogmartin
Is the timing, pace and success of the monarch migration associated with sun angle? Is the timing, pace and success of the monarch migration associated with sun angle?
A basic question concerning the monarch butterfly’s fall migration is which monarchs succeed in reaching overwintering sites in Mexico, which fail—and why. We document the timing and pace of the fall migration, ask whether the sun’s position in the sky is associated with the pace of the migration, and whether timing affects success in completing the migration. Using data from the Monarch...
Authors
Orley R. Taylor, James P Lovett, David L Gibo, Emily L. Weiser, Wayne E. Thogmartin, Darius J. Semmens, James E. Diffendorfer, John M. Pleasants, Samuel Pecoraro, Ralph Grundel
Arctic Shorebird Population Model Arctic Shorebird Population Model
This R script will run one example of the stochastic matrix models run by Weiser et al. (2020) to simulate shorebird populations. The model predicts population growth rates and elasticity values of vital rates. The example script is stand-alone and contains input values for one example species; input values for the other species are provided in the manuscript.
GRTS for Integrated Monarch Monitoring Program Code GRTS for Integrated Monarch Monitoring Program Code
These scripts prepare input files and run a Generalized Random Tessellation Stratified (GRTS) draw to select sampling locations for the Integrated Monarch Monitoring Program in the U.S., Canada, and Mexico.